1. Field of the Invention
The present invention relates to an automotive weather strip, and particularly relates to a door weather strip which has an extruded portion made of rubber and a molded portion made of rubber or thermoplastic elastomer, and which is attached to a vehicle by a double-sided adhesive tape or a bonding agent.
The present application is based on Japanese Patent Application No. Hei. 11-352323, which is incorporated herein by reference.
2. Description of the Related Art
A conventional weather strip is attached to the circumferential place of a door of a vehicle so as to seal between the door and a door opening portion of a body which is a partner-side member. Straight-line portions of such a weather strip are formed by an extrusion molding method while corner portions thereof having a small curvature radius are formed by a molding method. (For example, see JP-U-1-168346, JP-U-2-26934, etc.)
A door weather strip will be described by way of example. The weather strip has a base portion to be attached to the circumferential place of a front door, and a hollow seal portion extending from the base portion. For example, the weather strip is made of EPDM solid rubber or sponge rubber.
FIG. 12 is a cross sectional view showing the configuration of a conventional weather strip for a front door. This weather strip 50 is bonded with the outer circumferential place of a door frame 12 through a double-sided adhesive tape 55 and clips (not shown). A seal portion 52 having a hollow portion 54 is formed integrally with a base portion 51 of the weather strip 50. The hollow portion 54 is pressed by a body-side member 26 at the circumferential place of a door opening portion so as to be deformed and squashed. Thus, sealing is attained between the door frame 12 and the body-side member 26. Further, hollow portion 53 is formed in the base portion 51 separately from hollow portion 54 of the seal portion 52. A seal lip 56 and a rear lip 57 are formed integrally with the car-exterior-side wall surface of the base portion 51 not only in order to prevent noise from being produced by the wind at the time of high-speed driving, but also in order to perform sub-sealing. Alternatively, a head portion of a clip (now shown) may be inserted into the hollow portion 53 from the back surface side of the base portion 51 so as to be locked therein. Then, the clip is engaged with an engagement hole formed in the door frame 12 so that the weather strip 50 is attached to the door frame 12.
In the weather strip 50 described above, the contact bonding of the double-sided adhesive tape 55 to the door frame 12 is achieved by pressing the seal portion 52 to thereby squash the two hollow portions 53 and 54. Accordingly, there is a problem that the work of bonding is very difficult and troublesome to do, and the pressing force is not transmitted sufficiently. Thus, it is difficult to ensure the adhesive strength.
In addition, the seal portion 52 is compressed by the body-side member 26 when the door is closed. Since sealing is attained by such a configuration, it is necessary to increase the rigidity of the root of the seal portion 52. It can be therefore considered that the base portion 51 is formed to be so thick and the root position of the seal portion 52 is made so high that the rigidity of the root of the seal portion 52 is increased. However, if the base portion 51 is made thick, the shape of the base portion 51 becomes unstable due to the imbalance in thickness with other portions at the time of molding operation. In addition, extra material is required. Further, because there is no portion into which the head portion of the clip is inserted and locked, it is necessary to provide the hollow portion 53 in the base portion 51 separately. Thus, there is a problem that the weather strip becomes complicated to manufacture. That is, in the process of extruding unvulcanized rubber for forming the weather strip 50, it is necessary to adjust the respective pressures of the hollow portion 53 and 54 having different sizes, separately from each other, when the shapes of the hollow portions 53 and 54 are stabilized while preventing the seal portion 52 from being deformed and squashed due to the difference in pressure between the hollow portions 53 and 54 and the atmosphere around them. Therefore, there occurs a problem that the work of the adjustment is difficult. Further, when the sectional configurations of the extruded portion becomes complicated, there is another problem that the structures of molds for molded portion for connecting the end portion of the extruded portion with each other also become complicated so that the productivity is lowered.
It is a first object of the present invention to solve the foregoing problems belonging to the background art, that is, to provide an automotive weather strip which can be accurately and easily bonded with, for example, an attachment member of a body-side member, a door frame, or the like, at the circumferential edge of an opening portion of a door by a double-sided adhesive tape or a bonding agent.
In addition to the first object, it is a second object of the present invention to provide an automotive weather strip with the productivity improved.
Further, in addition to the above objects, it is a third object of the present invention to provide an automotive weather strip in which the sealing performance can be made uniform all over the circumference of the automotive weather strip.
Further, it is a fourth object of the present invention to provide an automotive weather strip which can be manufactured easily and can be bonded with a door frame by a compact double-sided adhesive tape, and in which the sealing performance can be made uniform all over the circumference of the automotive weather strip.
In order to solve the above problems, there is provided an automotive weather strip comprising a base portion and a hollow seal portion projecting from the base portion, the automotive weather strip being interposed between a body-side member and a door frame so as to seal off the body-side member from the door frame; wherein a flat-plate-like extended portion is formed on at least one of opposite left and right sides of the base portion, and a back surface of the extended portion is designed to be able to be bonded with a door or a body by a double-sided adhesive tape or a bonding agent.
Only one hollow portion is preferably formed in the seal portion.
A seal lip is preferably formed as a sub-seal portion integrally with an outside portion of the extended portion.
The weather strip may be formed into an annulus which can be attached continuously to an outer circumference of a front or rear door; the weather strip is constituted by an upper extruded portion and a lower extruded portion; the upper extruded portion has a seal lip as a sub-seal while the lower extruded portion has no seal lip; and the upper and lower extruded portions are connected integrally with each other through at least one molded portion having one hollow portion.
A groove for receiving the double-sided adhesive tape is preferably formed in a back surface of the extended portion.
Further, there is provided an automotive door weather strip comprising a base portion and a hollow seal portion, the base portion being attached to an outer circumference of a door frame by a double-sided adhesive tape; wherein: the base portion is shaped into a flat plate; the seal portion projects from the base portion and has only one hollow portion.
The weather strip preferably includes an extruded portion and a molded portion, the extruded portion and the molded portion being connected integrally with each other, and a core drawing slit for forming a hollow portion in the molded portion is formed in a base portion of the molded portion.
Features and advantages of the invention will be evident from the following detailed description of the preferred embodiments described in conjunction with the attached drawings.